Power transmission



Aug. w T DUNN ET AL rowan TRANSMISSION- Filed Nov. 26, 1937 5Sheets-Sheet 2 INVENTO M'Z'Zz'am 7, flanrz y 02 2 0 144K021. fl ATTORNEYAug. 29, 1939. w. T. DUNN ET AL POWER TRANSMIS S ION Filed Nov. 26, 19375 Sheets-SheetS I e I T. N NH R 5W O mum Wm 50m I. m

Aug.- 29, 1939..

W. T. DUNN ET AL POWER TRANSMISSION 5 Sheets-Sheet 5 Filed NOV. 26, 1937Patented Aug. 29, 1939 UNITED STATES PATENT OFFICE Mich, Highland Park,ware assignors to Chrysler Corporation, Mich., a corporation of DelaApplication November 26, 1937, Serial No. 176,607

19 Claims.

Our invention relates to power transmission mechanism and refers moreparticularly to improvements in. power transmission systems especiallyadapted for use in connection with motor 5 vehicles, although notnecessarily limited thereto.

The invention, in certain more limited aspects, provides improvements inthe drive and control for power transmission systems having epicyclic orplanetary gear trains. It is customary with such planetary transmissionsto arrange the gearing to provide for the desired number of speed ratiosbetween the engine and the vehicle driving ground wheels, and suchgearing is customarily selected and controlled to obtainthe desireddriving speed ratio by actuation of any one of a group of transmissioncontrolling devices usually consisting of reaction brake bandsassociated with and controlling the rotation of corresponding drums orsimilar elements of the various gear trains.

One object of our invention is to provide a novel and inexpensive meansfor effecting, in. response to the selection of a speed ratio, thedesired degree of engagement of the selected speed ratio controllingdevice of the transmission.

Another object of our invention, in certain more limited aspects,resides in the provision of a pump pressure regulating means whicheffects the desired fluid pressure for actuating the pressure operatingmeans to properly control the brake bands and clutches of the planetarygear trains or other corresponding types of transmissions in response tothe selection of a speed ratio controlling device of the transmission.In the broader aspects of our invention, the fluid pressure ispreferably provided by a suitable liquid medium such as oil, but thefluid pressure medium may be air under pressure greater or less thanatmospheric pressure.

A further object of our invention is to provide a simple and efficientmeans for regulating the well-known swash plate pump-of such type as isdescribed and claimed in the copending application of Augustin J.Syrovy, Serial No. 29,788, filed July 5, 1935in order to provide, inresponse to the selection of a transmission speed ratio, the propermaximum fluid pressure to effect the degree of engagement of theselected transmission speed ratio controlling device necessary tocontrol the torque transmitted by the selected speed ratio.

A still further object of our invention resides in the provision ofmultiple level-01f pistons to regulate the inclination of the swashplate of the well-known swash-plate pump, in response to the selection.of a transmission speed ratio, to effect the fluid pressure necessaryfor the operation of the selected speed ratio controlling device tocontrol the torque transmitted by the selected speed ratio.

Another object of our invention is to provide a pressure regulatingmeans to regulate the swashplate pump in response to the selection of atransmission speed ratio, to eifect the fluid pressure necessary for theoperation of the selected speed ratio controlling device to control thetorque transmitted by the selected speed ratio, and to simultaneouslydeliver said necessary fluid pressure to the operating means for saidselected speed ratio controlling device.

Further objects and advantages of our invention will be apparent fromthe following detailed descriptions of several illustrative embodimentsof the principles of our invention, reference beinghad to theaccompanying drawings in which:

Fig. 1 is a side elevational view, somewhat diagrammatic in form,illustrating our power transmission mechanism as a whole.

Fig. 2 is a detail elevational view showing the manually controlledselector element and the well known foot-operated clutch, brake andaccelerator pedals of a motor vehicle.

Fig. 3 is a sectional view of the manually controlled selectingmechanism taken as indicated by the line 3--3 of Fig. 1.

Fig. 4 is a sectional view along the line 4-4 of Fig. 3.

Fig. 5 is an enlarged sectional view taken approximately as indicated bythe line 5-5 of Fig. 1.

Fig. 5A is an enlarged detail sectional viewtaken along the line 5A5A ofFig. 5.

Fig. 6 is an enlarged sectional view taken along the line 6-6 of Fig. 1through the transmission and fluid clutch.

Fig. '7 is a vertical sectional view through the transmission,illustrating one of the speed ratio controlling devices and partsassociated therewith, the section being taken as indicated by the line|-'I of Fig. 6.

Fig. 8 is a vertical elevational view illustrating the housing mechanismfor the fiuid pressure operator and associated control valve, the viewbeing taken approximately as indicated by the line 8--8 of Fig. 6.

Fig. 9 is a detail sectional view taken along the line 99 of Fig. 8.

Fig. 10 is a detail vertical sectional view taken approximately asindicated by the line lfl--lll of Fig. 6.

Fig. 11 is a detail sectional view of the transmission pump and aportion of our pressure reg- 3| with the B so that even when the drivenvane member 22 ulating means, the section being taken as indi cated bythe line Hll of Fig. 1.

Fig. 12 is a diagrammatic view illustrating the electrical system ofcontrol between the manually operated selector element and the fluidpressure control valve mechanism.

Fig. 13 is an enlarged sectional view taken approximately as indicatedby the line i3l3 of Fig. 1.

Fig. 14 is a detail sectional View taken along the line ll4 of Fig. 13.

Fig. 15 is a detail sectional view taken approximately as indicated bythe line 15-45 of Fig. 11.

Fig. 16 is an enlarged horizontal section taken along the line 16-16 ofFig. 1.

Fig. 1'1 is a side elevational view corresponding to Fig. 1 butillustrating another embodiment of our pressure regulating means.

Fig. 18 is a fragmentary vertical sectional view somewhat diagrammaticand illustrating one of the planetary transmissions speed ratio brakecontrolling devices, the section being taken along the line l8-l8 ofFig. 17.

Fig. 19 is an enlarged vertical sectional view taken approximately asindicated by the line 19-49 of Fig. 17.

Fig. 20 is an enlarged view of the valve mechanism shown in Fig. 1'7.

Referring now to the drawingswe have illustrated our invention inconnection with a motor vehicle drive, this drive including a primemover or engine A, a portion of which is shown in Fig. 1, a main clutchB driven from the engine, and a change speed transmission or gear box Cdriven from the clutch B. The drive passes from. the transmissionthrough the power take-off shaft 20, which, as usual, may extendrearwardly of the vehicle to drive the usual groundwheels (not shown).

4 The clutch B may be of any suitable construction for controlling thedrive between engine A and transmission C, this clutch being illustratedin Fig. 6 in the form of a fluid coupling type having the usual drivingand driven cooperating vane members 2! and 22 respectively. The drivingvane member 2! is carried by the engine flywheel 23, the latter beingconnected as usual with the rear end of the engine crankshaft 24. Thedriven vane member 22 is splined to a hub 25 which in turn is splined at26 on the forward end of the driven shaft 21. This driven shaft extendsrearwardly to drive the power take-01f shaft 29 through the intermediaryof the various gear trains of transmission C.

Where the power means for operating the transmission is afforded by afluid such as oil under pressurathe pump for placing the oil underpressure is preferably operated from the engine to maintain the fluidpressure even when the pump is idling. It is therefore preferred toprovide a pump drive from the driving clutch member 21 rather than thedriven clutch member 22 inasmuch as the latter may be stationary undercertain conditions of vehicle operation such as when the vehicle isstanding still with the engine idling.

This pump drive may be provided by reason of a driving sleeve or hollowshaft 29 mounted on the shaft 21 but rotatable independently thereof.The sleeve 29 has a hub 01 flange 30 connected at driving vane member 2|of the clutch is not being operated from the driving vane member 2|, thesleeve 29 will be rotatably driven from the engine crankshaft 24 andflywheel 23. The

pump drive from sleeve 29 will be more apparent hereinafter.

We have illustrated the fluid type of clutch B since a clutch of thischaracter has a number of advantages in connection with a transmissionof the planetary gear type C and in further connection with ourarrangement of vehicle driving controls which will be presentlydescribed more in detail. Among the advantages of the fluid type ofclutch are the provision of a smooth drive for the vehicle through theplanetary transmission, relatively high power driving efiiciency,automatic release of the drive between the engine and transmission whenthe engine is idling, and with the transmission manipulated to establishone of its driving gear ratio settings, and other well known favorablecharacteristics. We desire to point out, however that other types ofclutches may be employed to control the drive between engine A andtransmission C within the broader aspects of our invention. For example,the well known type of friction clutch may be employed and manuallyoperated or automatically operated by the Well known commercial type ofvacuum clutch releasing mechanism as will be readily understood.

We have illustrated the change speed transmission C as the epicyclic orplanetary type, this general form of transmission being well known inthe art and, as usual, includes a plurality of transmission speed ratiocontrolling clutches or brakes 32, 33, 34 and 35, these brakingcontrolling devices being respectively adapted to actuate thetransmission in its first speed ratio or low gear, second speed ratio orintermediate gear, third speed ratio or direct drive, and reverse drive.Other speeds may be provided as desired.

The typical brake device 32 illustrated in Fig. 7 consists of an outerband 36 which substantially surrounds the rotary element or drum 31, theband being provided with friction braking material 38 carried by theband and adapted for frictional engagement with the drum 31. The band 36has its ends formed with laterally projecting actuating flanges 39 and40 positioned adjacent each other, means being provided to move the bandends toward each other to contract the band 36 for causing the frictionmaterial 38 to brake rotary drum 31, the band having sufficient inherentresilience to expand away from contact with the drum when the actuatingmeans is re lievecl at the flanged ends 39 and 4!). In Fig. 7 the lowspeed ratio braking devices 32 is illustrated inits inoperative positionwhereby the drum 31 is free to rotate through operation of the planetarygear set t! somewhat diagrammatically illustrated in association withthe drum 31. When the braking device 32 is actuated by contracting theband 33, the drum 31 is held against rotation, the driven shaft 29 insuch instance being operated through the planetary gearing 4| to providethe low speed drive for the motor vehicle.

In order to anchor the band 36 and to substantially equalize the brakingforces applied to drum 31 around the periphery thereof and thereby substantially avoid a tendency toward lateral loading of the drum andplanetary gearing transverse to the axis of the drum, we have providedthe band With a circumferentially spaced pair of anchoring flanges 42.These flanges are connected through links 43 with the levers 44pivotally mounted at 45 with the supporting bracket 46 of thetransmission side cover casing 41, the levers 44 being interlocked at 48so that movement of in the transmission casing.

one of the flanges 42 will be transmitted through the pivotal levers 44and the links 43 to the other portion of the band associated with theanchoring device. The links 43 are thus pivotally connected at theiropposite ends respectively with the anchors i2 and levers 44.

The third speed clutching controlling device 34 is arranged for a directdrive through the transmission and differs somewhat from the brakingdevices 23, 33 and 35 in that the controlling device 35 has its rotarycontrolling element 58 adapted for clutching action in a well knownmanner by frictional engagement through the discs 5i by an axiallymovable clutching member 52. The latter clutching member is thus engagedby the yoked end 54 of an actuating lever 55 piv otally mounted by a pin56 suitably supported n the opposite side of pivot 56 the lever 55 isprovided with a step actuating portion 58, the purpose of which willpresently be more apparent.

The transmission casing portions 58 and 58 are respectively providedwith the vertically spaced inwardly extending supporting brackets 62 and83, respectively, these brackets being formed with coaxial splinedopenings 55 and 55, respec tively. Splined within these openings are thenuts 65 and 6'! which are axially and oppositely threaded to receive thecorrespondingly threaded ends 68 and 59 of an operating oscillatoryshaft or screw '10. V

The shaft ll] extends through openings H and 12, respectively, formed toopen laterally in the aforesaid band ends 38 and 45, these openingshaving considerable clearance with shaft 10 so as not to bind on theshaft when the band is contracted and expanded. In order to transmit thethrust of the nuts 65 and 81 to the flanges 38 and 40 so as to relievedistorting loads on the shaft 10 and parts associated therewith, eachnut operates a sleeve 13 having a curved face 14 engaging a curved face75 of band end 38 or 48. The engaged curved faces '14 and f provide arocking freedom of action, each sleeve 13 having a clearance indicatedat 16 with the shaft H3.

The operating shaft 78 of the low speed braking device 32 has itsportion thereof intermediate the band ends 39 and 48 formed with a gear11, the means for oscillating shaft 18 through the gear 11 beinghereinafter more particularly described.

In the operation of the low speed controlling device 32 as thus fardescribed, it will be apparent that when the shaft 78 is given a rotarymovement, such movement operates through the oppositely threaded ends 88and 59 of the shaft 18 to cause the nuts 85 and El to move inwardlytoward each other in their splined openings 64 and 65 respectively, thismovement acting through the sleeves 13 to contract the band ends 39 and48 whereby the low speed drum 3'! has its rotation checked forestablishing the low speed drive through the transmission. When theshaft 2!! is rotated in the opposite direction, the nuts 85 and 81 aremoved away from each other and the band 36 is expanded to permit thedrum 3'! to again rotate and thereby relieve the drive through thetransmission controlling device 32.

In order to avoid repetition we have not illustrated all of the detailsof the brake operated means associated with the controlling devices 33and 35, it being understood that such operating means are similar tothat described in connection with the controlling device 32. Forconvenience of reference the operating shaft or screw for the reversespeed braking device is designated as Hl and the corresponding shaft forthe second speed braking device 33 is designated as The gears associatedwith these screw shafts are respectively designated as 'l! and 11 Aswill be more apparent, presently, the gears 11, 11 and 11 and lever end59 are adapted to be selectively operated in order to selectivelycontrol the engagement and release of the respective speed ratiocontrolling devices 32, 35, 33 and 34.

The transmission casing is adapted to support in a forward opening 18the reciprocating and oscillating rack or actuating shaft D. The rearbearing for shaft D is provided by a member 19 which is disposed in asuitable opening 88 in the rear end wall 8! of the transmission casing8|, the rear end of the actuating shaft D being also supported by apiston for reciprocating the shaft and which will presenty be referredto in detail.

This actuating shaft D has a series of teeth forming a rack adapted tobe brought into operative association with each of the screw gears,these racks being designated at 82, 83 and 84 for respectively operatingthe screw gears Tl, TI and H The forward end of shaft D is further prvided wtih a third speed actuating projection 85 adapted for engagementwith the lever shoulder 59 for operating the third speed controllingdevice 34. It will be noted that the racks and projection 85 arelongitudinally spaced along the shaft D and that they are also spacedcircumfer entially of the shaft whereby upon progression rotation of theshaft only one of the racks and the projection 85 will engage itsassociated screw gear or lever 55 at any time.

In Figs. 6 and '7 it will be noted that the shaft D is positioned sothat the low speed rack 82 is in position for operating the low speedgear 11 and when the shaft D is moved forwardly or to the left as viewedin Fig. 6, the low speed screw 10 will be rotated to cause the aforesaidbraking operation of the low speed controlling device 32 forestablishing the low speed drive through the transmission. It willfurthermore be noted that with the low speed rack 82 in the positionillustrated, the remaining racks Z3, 84 as well as projection 85 arefree from engagement with their respective associated gears Il 11 andthe lever 55. From Figs. 6 and '7 it will be noted that the shaft D hasa space longitudinally and circumferentially between the second speedrack 84 and the direct drive projection 85, this space being designatedas the neutral space N so that when the shaft is positioned with thisspace facing the screw gears, each of the racks as well as projection 85will be free from contact with their associated screw gears and lever55, and the transmission will be in neutral at which time the variousbraking devices 32, 33, 34 and 35 are released.

In order to selectively rotate the rack D for selectively engaging theracks and projection 85 thereof with the respective screw gears and1ever 55, and also for axially operating the shaft in the variouspositions of selective adjustment, the following mechanism is provided.

Rearwardly adjacent the reverse rack 83, the shaft D is provided with acircular rack or gear 86 meshing wth a segmental rack 81 rotatably fixedwith a shaft 88, best shown in Fig. 7, this shaft being rotatablyjournaled by a bearing 89 carried by the transmission side cover 88. Theshaft 88 has fixed thereto, outwardly of the transmission cover, a lever9! connected at 92 (see Fig. 1) to a Bowden wire operating mechanism 93.

The Bowden wire operating mechanism 93 extends forwardly for pivotalconnection with a ball end 94 of a lever assembly 95 secured to atubular shaft 96 as shown in Figs. 5 and 5A. The

forward end of the Bowden mechanism has a guide 97, provided by thebracket 93 rigidly secured to the outer stationary tubular housing 99comprising the steering post, as best shown in Fig. 1. A yieldingconnection is preferably provided at some convenient point between themanual selector element, which will be shortly described, and thesegmental rack 8'! for rotatably adjusting the shaft D. We haveillustrated this yielding connection in Fig. 5A intermediate the leverball end 94 and the forward end of the Bowden wire mechanism 93. Thewire 93 is anchored at its forward end to a housing IEO provided withpreloaded oppositely acting springs IfiI and I92 which respectively actagainst the ball seats I93 and ltd. The springs IEBI and I02 havesufficient rigidity so that normally they provide a rigid connectionbetween lever 95 and 'Bowden wire 93. However, if for any reason themanually operated adjusting mechanism for the shaft D should bind at anypoint, the mechanism will be protected during any manual adjustment oflever 95 under such conditions by reason of the ability of springs IiiIand I02 to yield. This yielding connection is therefore in the nature ofa safety device for the manually controlled selector operatingmechanism. The hollow operating shaft 96 extends within the housing 99and is suitably rotatably journaled therein.

Botatable within the hollow shaft 93 is the hollow steering shaft I97operably connected at its upper end to a steering wheel I98 and adaptedfor operable connection at its lower end to the usual steering mechanismfor the front ground wheels of the motor vehicle (not shown). The hollowoperating shaft 96 extends'upwardly to the point preferably just belowthe steering wheel I93 to the manually controlled device generallydesignated at E for selectively controlling or manipulating thetransmission speed ratios as will be presently more apparent.

Returning now to Fig. 6, the selector rack shaft D has its rear endadjacent the circular rack 86 provided with a groove I 99 adapted toreceive the flange III] of the fluid pressure operating'piston assemblyI I I adapted for reciprocable movement in the cylinder H2 which is apart of a casting H3 best illustrated in Figs. 8 and 9 as attached atlid to the rear wall of the transmission. The piston iII provides theactuating member of the power operating means G for moving shaft D underpower to engage the various brake bands and the direct speed clutch 34.

For yieldingly urging the rack shaft D to the right or rearwardly torelease the speed ratio controlling devices, we have provided primemover means F preferably in the form of a compression coil springsurrounding the rear end portion of shaft D between the fixed abutmentprovided for the bearing member I9 and acting on piston III. In Fig. 6it will be noted that the bearing member 19 is conveniently held inposition by clamping the same between the rear casing wall 8! of thetransmission and the casting assembly H3.

The piston III has a flexible sealing cup II5 adapted to seal the pistonagainst escape of the fluid forwardly of the cylinder H2, the cup I I 5bearing against the walls of the cylinder under the action of the fluidpressure introduced to the pressure chamber H6. The sealing cup is heldin place by the rearwardly extending threaded reduced fastener or nutH8. Fluid, such as oil under pressure, is introduced to the pressurechamber II6 as best shown in Fig. 9, through a passage I I9 leading tothe valve controlled chamber or cylinder I29 which slidably receives thefluid pressure supply controlling valve I2 I The cylinder I20 issupplied with oil under pressure through a passage I22 which receivesthe oil by a conduit I23 formed in the transmission casing casting. Theconduit I23, as best shown in Fig. 1, leads to the delivery side of aswash-plate type pump H driven from its location in the oil storing sumpor reservoir I24 of the transmission casing by reason of the shaft I25provided at its forward end by a driving gear I23. This gear meshes withan idler gear I2'I which in turn meshes with the driving pinion I28 (seeFig. 6) carried on the rear end of the driving sleeve 29 which, asaforesaid, is fixed to the fluid impeller 2I.

A valve guide porting member I29 is pressed into the cylinder I29 so asto be fixed therewith, this porting member having annular conduits I39and I3I, respectively, communicating with the passages I22 and H9. Theannular passages I39 and I3I are also respectively provided with theinwardly extending ports I32 and I33 adapted for control by the valve I2I. This valve has a sliding fit within the cylindrical bore I34 of theporting member I29 and extending axially through the valve withsuflicient clearance to prevent binding thereof, is a valve operatingrod I35 preferably of brass or other non-magnetic material. The rod I35extends forwardly of valve I2I and is provided with a stop I36 adaptedto limit forward movement of valve I2I under the influence of a springI3! which operates between a valve spring abutment I38 and a rear fixedabutment I39, the latter having associated therewith the fluid pressuresealing washers I40 acting against the threaded stem I4I of theelectrical solenoid I42.

The rear end of valve operating rod I35 is connected at I43 with thearmature I44 of solenoid I42, the armature being adapted forreciprocation in the solenoid cylinder I45 having the rear abutment I46.Any fluid which may leak rearwardly beyond the valve I2I is adapted todrain downwardly from the portion of casting H3 which encloses the valveoperating spring I3'I by reason of the drain conduit I41, this conduitthen extending forwardly to the main body of the transmission where theoil is permitted to drain back to the reservoir I24. A further conduitI43 is adapted to return the oil from operating cylinder I I6 back tothe reservoir, this conduit I 58 opening rearwardly to the forward endof valve I2I.

The valve IZI has the reduced valving portion I49 adapted to place theconduits I22 and H9 in communication when the valve is in its forwardposition under the influence of spring I31. In the drawings, the partsare shown in their positions for operating the low speed controllingdevice 32, the valve I2I being positioned forwardly so that the fiuidpressure is just being delivered from the supply conduit I22 to theconduit H9 and the pressure chamber II 6 of the cylinder H2. When thevalve I2I moves rearwardly under the influence of solenoid I42, as willbe presently more apparent, the spring I3'I will be compressed and thereduced portion I49 will no longer provide communication betweenconduits I22 and H9 to supply fluid pressure from the pump H to operatethe piston III and selector rack shaft D forwardly for actuating one ofthe speed ratio controlling devices 32, 33, 34 or 35, depending on therotative selective adjustment of the selector rack shaft, as will bepresently more apparent.

The function and operation of the manually controlled selector mechanismE in relation to the selector rack shaft D will now be furtherdescribed.

Secured to the upper end of the hollow operating shaft 96, as best seenin Fig. 4, is an annular collar I50 having an integral laterallyextending projection I! providing an abutment for a spring I52 which hasits lower end yieldingly acting against an intermediate portion of amanually operated selector element or lever I53. It will be noted thatthe extension I5I projects through an arcuate opening I54 of the fixedhousing 99 to accommodate oscillating adjustment of the extension I5I.

The inner end of selector lever I53 is pivotally mounted at 155 to anintermediate portion of the collar extension I5I so that the selectorlever may have vertical movement on pivots I55 relative to the extensionI5I but when lever I53 is moved around the axis of the steering posthousing 99, the collar I55 together with its extension I5I and the shaft66 will be rotatively moved as a unit.

Fixed on the upper end of the housing 39 is a housing I56 preferably inthe shape of a sector. The outer end of this housing has a downwardlyextending flange I51 provided with an arcuate opening I53 through whichthe lever I53 extends for arcuate adjustment. The outer end of theselector lever is provided with a knob or handle I59 adapted forconvenient grasp by the hand of the motor vehicle driver.

The outer curving edge of housing I56 is pref-v erably formed with anumber of legends charac terizing the various positions of manualadjustment of selector lever I53 depending on the number of stations ofadjustment for this lever. In the particular embodiment illustrated, theselector lever I53 is adapted to have five positions of adjustment I60,I6I, I62, I63 and I64 bearing the legends indicated in Fig. 3designating the lever positions corresponding to first, second, third,neutral and reverse conditions of control for the transmission.

The flange I51 of housing I55 carries an arcuately arranged switchmechanism below the selector lever I53, this mechanism being bestillustrated in the wiring diagram of Fig. 12. This switch comprises anarcuate floor I65 provided with a series of grooves or notches I66, I51,I68, I69 and HI! corresponding respectively to the positions of selectorlever I53 when adjusted to the stations I60 to I64, inclusive. The uppersides of the aforesaid notches are preferably chamfered or beveled, asshown in Fig. 12, and the portion of selector lever I53 engageable withthese notches is likewise beveled as indicated at "I.

When the operator desires to select any condition of control of thetransmission, he swings the selector lever I53 into the desiredposition, the spring I52 yieldingly urging the selector lever downwardlyinto engagement with one of the notches of the switch member I55.

Referring now to the wiring diagram of Fig. 12, a plurality of switchesor contacts I12 for each of the notches of the switch member I65 areadapted for operation by a stem I13 slidable in an opening I14communicating with each of the switch notches. When the selector arm islocated in any of the switch notches, one of the stems I13 associatedwith such notch is engaged by the selector lever and is pusheddownwardly by the spring I52 to break the current through the wire I15which connects all the switches I12 in series. Each switch I12 has aspring I16 associated therewith for restoring the switch to itscontacting position and raising its stem I13 as soon as the selectorlever is moved out of one of the notches. The wire I15 connects with oneterminal of a storage battery I11, the other end of the wire 115 beingconnected to the windings I13 of the solenoid armature I44 aforesaid,which is grounded at the other terminal of the battery I11.

The manually controlled selector operating mechanism is practicallyinstantaneous in its response to selective adjustment of the lever I53and the different selections may be made as rapidly as. desired. In thegeneral operation of the selector mechanism E for changing thetransmission speed ratio, the operator moves the selector lever I53 fromone of the station notches in the switch member I65. Just as soon as theselector lever is moved from one of the notches, the switch I12associated with such notch will be closed, thereby inducing anelectrical circuit through the solenoid windings I18 for causing thesolenoid armature I44 to move rearwardly against the abutment I45. Thisrearward movement of the solenoid armature will adjust the valve I21rearwardly to place the fluid pressure chamber II6 of cylinder H2 incommunication with the reservoir discharge conduit I48 whereupon thespring F will move the shaft D rearwardly to release any of thecontrolling devices 32 to 35 which might have been in operation. Thisentire phase of the operation takes place very quickly during theinitial part of adjustment of the selector lever out of one of thenotches of the switch member I65. The selector lever I53 may then bemoved into any other station of control and dropped into thecorresponding notch for such position.

When the selector lever is so released it will be apparent that one ofthe switches I12 corresponding to such newly selected position will beopened, thereby interrupting the electrical circuit through the wire I15to the solenoid windings I18. At such time the spring I31 willimmediately act to move the valve I2I and the armature I44 forwardly toestablish communication between the fluid pressure supply conduit I22and the pressure chamber H5. This will immediately cause a forwardmovement induced by the fluid pressure on the shaft D for operating oneof the selector controlling devices which might have been selected forthe new position or else for operating the shaft D without causing anymovement of any of the speed ratio controlling devices in the event thatneutral was selected.

Returning now to the aforesaid cycle of operation and to the point wherethe selector lever I53 was described as having been moved out of one ofthe notches preparatory to movement through the hollow steering postshaft I01, Bowden wire mechanism H2, and sector 81 to rotatably adjustthe shaft D into a new position for actuation of one of the speed ratiocontrolling devices. The mechanism operates almost instantaneously sothat there is practically no resistance to immediate arcuate adjustmentof the selector lever I53 from a position in one of the notches althoughany binding tendency experienced at the shaft D during the initial orother tendency to move the shaft will be taken up yieldingly through theBowden wire connection shown in Fig. A.

With reference now to the details of the pump H and our pressureregulating means, the pump assembly includes a casing structure I19fixed to the transmission structure as illustrated in Figs. 1 and 11.The casing I19 receives the pump drive shaft I25 which is suitablyjournalled at I 88 and I8I by the casing.

As illustrated the gear I26 on the shaft I25 is in constant mesh withthe idler gear I21 which in turn is drivingly connected with thefluid-impeller-associated driving pinion I28. A ported cylindricalmember I 82 is suitably fixed to the casing I19, the member I82 havinginlet and outlet passages I83 and I84 respectively for the fluid, suchas oil, admitted to the pump H and delivered therefrom under pressure.The inlet I 83 is in suitable communication with the fluid in thereservoir I24.

Tightly pressed into a cylindrical opening I85 of the ported member I82is a cylindrical port seat body or ring I86 journ-alling the adjacentend of the shaft I25, this body having inlet and outlet passages I81 andI88 communicating radially at one end with the passages I 83 and I84respectively. The other ends of the passages I81 and I88 form the wellknown circumferentially spaced arcuate inlet and outlet portsrespectively for communication with the inlet and outlet ports of thepumping cylinders as will presently be apparent.

A pump rotor I 89 is drivingly connected to the shaft I25 and carries aplurality of circumferentially spaced cylinders I98 opening inwardlytoward a wabble or swash plate I 9|, a cylinder head portion I92 of therotor having a port I93 for each cylinder.

A piston I94 is'adapted to reciprocate within each cylinder I98 and isurged rearwardly by a spring 195 into contact with the swash plate 595.The rearwardly extending rounded end of each piston yieldingly engagesan outer ring I96 of the swash plate. This'ring is supported by abearing I91 carried by a swinging arm I98 pivotally supported at I99from the casing I19.

The swash plate I9I carries a yoke extension 288 which is adapted to becontrolled by multiple pressure pistons 28I, 292 and 283 in its swingingmovement about the support I99 for levelling off the plate I9! andminimizing or eliminating reciprocation of the pistons I94. Apluralityof parallel cylinders 284, 285 and 286 are provided by the casing I19 toaccommodate the pistons 28I, 282 and 283, respectively. Each of thepistons 28I to 283 carries a stem portion 291 suitably fixed to a yokedend member 288 by a pin- 289. Shoulders 2I8 of the member 288 (bestshown in Fig. 15) are positioned adjacent to the arms of the extension288.

An end plate 2II is fixed by fasteners 2| 2 to the casing I19 to closethe rearward ends of the cylinders 284 to 286 and thus provide pressurethrough pressure conduits 2I4, 2I5 and 2I6 respectively, as willhereinafter be more apparent.

A cylindrical valve sleeve 2E1 is preferably carried by the casing Biand receives the conduits 2I4 to 2I6. Within the sleeve 2I1 a valve 2I8is adapted to reciprocate in response to manipulation of the selectorarm I53. Thus a rack extension 2!!) of the valve 2I8 receives verticalmovement in response to rotation of a pinion 228 carried by the rack D.

The relation of the rack pinion 220 to the valve 2I8 is such that whenthe selector arm I53 is in its illustrated first speed position thevalve places a pressure conduit 22! of the sleeve M1 in communicationwith the conduits 2M and 2I5. When the selector lever E53 is adjacentits second and third speed stations I6I and I62 respectively the valve2I8 effects a communication between the conduit 22I and the conduits2I4, 2I5 and 2I9. Upon swinging the arm I53 to its reverse station I64the valve 2I8 opens the conduit 22I to conduit 2I4. Suitable bleeds 222and 223 are provided in the sleeve 2I1 to return the escaping fluid tothe reservoir I24.

To provide a suitable fiuid pressure control for the conduit 22I toassist in making speed ratio selections with the selector arm I53, avalve 224 is adapted to progressively close the conduit 22! and place itin communication with the reservoir I2 l. The conduit 22I is received bya cylindrical valve casing 225 fixed to the casing of the fluid flywheelB. The valve 224 is adapted to move longitudinally within the casing 225in response to the actuation of a suitable remote control by the vehicleoperator. To this end, a link member 221 (best shown in Figs. 1 and 16)extends through a closely fitting end cap 228 to be fixed to the valve224 and has an articulated connection at 229 on the shorter arm. of apedal 238 pivotally supported at 23I on the casing of the fluid flywheelB.

A fiuid pressure conduit 232 is received adjacent to the conduit 22! bythe valve casing 225, and a reduced valve portion 233 of the valve 224is adapted to gradually close the conduits HI and 232. Upon additionalrearwardly movement of the valve 224, in response to further travel ofthe pedal 238 to the vehicle toe-boards 234, the conduits 22I and 232will be opened to a pressure relief conduit 234 in the valve casing 225communicating with the reservoir I24. The fiuid pressure conduit 232 isin constant communication with the pump: through the pressure deliveryconduit I23.

As the shaft I25 drives the rotor I89, with the plate I 95 in its Fig.11 position for maximum stroke of the pistons I94, approximately halfthe pistons i9 3 are moving inwardly drawing in oil through their inletport and ports I93 associated therewith, while the remaining pistons aredischarging oil under pressure through their associated ports I 93 andoutlet port for conveyance through the conduit I23 in the well knownmanner.

When the pump H is initially operated, the pressure of the fluiddelivered through the conduit I23 also communicates through theconduit232 and with the one or more of the pressure conduits 2M to 2I3providing the pedal 238 is in its illustrated position. t will beapparent fromv the disposition of the pistons 28I, 282 and 283 relativeto the wobble plate structure that the pump will deliver a greaterpressure in response to action of the pistons 28I and 282 than will bedelivered inresponse to action of the pistons 2M, 202 and 203 thereon,and that a still further increase in pressure will result from thepiston 2IlI acting singly. Thus, the pump is conditioned in response tomanipulation of the selector to deliver a pressure which willsatisfactorily and efficiently operate the selected speed ratio geartrain of the transmission.

Referring to the modified embodiment of the invention illustrated inFigs. 17 to 20, the pump pressure regulating means is illustrated with apressure system for a power transmitting device of the same generalcharacter as that of the earlier described embodiment except that thepressure medium is selectively admitted to individual pressure cylindersfor actuating the operating means for each speed ratio controllingdevice. Parts of similar function but different construction have beenindicated by primed reference characters.

The illustrated vehicle drive includes the prime mover or engine A, thefluid coupling clutch B driven from. the engine, and the change speedtransmission C" driven from the clutch B. During operation of thetransmission C the drive passes therefrom through the power take-01fshaft 20.

The change speed transmission C is of the epicyclic or planetary typeand includes the transmission speed ratio controlling devices 32', 33,34 and 35, these devices being respectively adapted to actuate thetransmission in its first speed ratio or low gear, second speed ratio orintermediate gear, third speed ratio or direct drive, and reverse drive.The aforesaid devices are adapted to act on transmission elementsassociated therewith and usually embodied in the form of a rotary drum31', which is illustrated in Fig. 18 in association with thetransmission controlling device 32 for the first speed ratio. Inasmuchas the form and arrangement of these planetary gear trains are wellknown in the art, the details thereof are omitted from this disclosure.

The speed ratio controlling devices are for the most part similar inconstruction and operation and the following description of the detailsof the controlling device 32' illustrated in Fig. 18 is typical of theother devices. In Fig. 18 the drum 31 is normally rotated by theplanetary gearing 4| associated therewith when the transmission is notin its first speed driving condition, and when rotation of the drum 31is prevented by the braking mechanism associated therewith, then thedrive through the transmission takes place for the first speed gearratio according to well known practices for planetary gearings of thegeneral type illustrated.

To brake the drum 31, the band 36 around the drum provides ends 235 and236 normally separated by a spring 231. The band is provided with thebrake lining 38 adapted to contact with the drum when the ends 235 and236 are forded toward each other for contracting the band. The band 36is anchored in any suitable manner (not illustrated) and a suitablebrake actuating mechanism is provided for each of the bands such as theactuating mechanism illustrated in Fig. 18.

Associated with each of the speed ratio controlling devices is acylinder, one of which is illustrated at 238 in Fig. 18 in associationwith the controlling device 32'. This cylinder receives a pair ofoppositely disposed pistons 239 and 240 operably connected to actuatethe respective band ends 235 and 236 by suitable links 24I pivotallysupported at 242. The cylinder has a fluid pressure inlet 243 adapted toadmit fluid under pressure to the space between the pistons 239 and 246in order to actuate these pistons away from each other as shown in Fig.18 in contracting the brake band to arrest rotation of the associatedcontrolling drum 31'. Upon release of the fluid pressure the spring 231will act to space the brake band 36 from the drum 31, pistons 239 and240 being restored and the fluid pressure being displaced from thecylinder 238 by way of the opening 243. e

In order to selectively control the supply of fluid under pressure tothe actuating mechanism of the various speed ratio controlling devicesprovision has been made for a fluid pressure control and distributingsystem, this system including a control mechanism, generally designatedby the letter J operable in conjunction with the pump I-I shown in Fig.11. The pump H is housed in a transmission casing 244 for actuation by avertical shaft 245 having a gear 246 meshing with a gear 241 drivinglyconnected with the driving sleeve 248 of the driving vane member 249; ofthe fluid coupling B. Fluid is drawn by the pump H from the reservoirI24 through the passage I83 and discharged through the high pressurepassage I84 leading to the control J.

The swash plate I9! is controlled by the pressure responsive pistons26I, 262 and 263, as set forth in connection with Fig. 11, pressurebeing supplied to these pistons from the control J for regulating thepressure of fluid delivered by the pump in response to manipulation of aselector mechanism generally designated by the letter M, as will behereinafter set forth.

The control J includes a casing 259 having a pair of cylinders 25I and252, arranged in parallel relationship, in which are disposedreciprocatory pistons 253 and 254 respectively. The piston 253 has areduced portion 255 which cooperates with the cylinder 25! to form achamber 256 to which fluid pressure from the pump outlet I84 is admittedby the inlet passage 251 in the cylinder 25L The cylinder 25! isprovided with ports 258, 259 and 266, through which fluid from thechamber 256 to the respective conduits 26I, 262, 263, the lattercommunicating fluid pressure to the pistons 26I, 262 and 203,respectively, for actuating the swash plate I9I. Fluid from the chamber256 is adapted to be communicated to the cylinder 252 through ports 264,265, 266 and 261 disposed opposite respective ports 268, 269, 270 and21I found in the wall of the chamber 252, the latter ports being adaptedto communicate fluid through respective conduits 212, 213, 214 and 215to the operating mechanism aforesaid of the speed ratio controllingdevices 35', 32', 33' and 34, respectively. The piston 254 has anannular groove 254 adapted to selectively communicate fluid from theports 264, 265, 266 and 261 to a respective port 268, 269, 216 and 2H.The piston 254 has a reduced portion 254 cooperating with the cylinder252 to form a chamber for receiving fluid returned from a cylinder 238,such fluid passing from the chamber through one of the ports 216, 216and 216 for return to the reservoir I24.

The valves 253 and 254 have stems 211 and 218, respectively portions ofwhich extend through the casing 250 and are connected by the member .219for simultaneous reciprocation by the selector mechanism indicated at M.

The mechanism J therefore constitutes a means by which 'fluid pressureis selectively distributed to the pistons L 202; and 263 for controllingthe pressure of fluid delivered by the pump H in response to theselective operation of one of the speed ratio controlling devices of thetransmission C. Operation of the mechanism J is controlled by theselector mechanism indicated at M.

The mechanism M is mounted upon the conventional steering column 285immediately adjacent the steering wheel 28 I. A segmental bracket 282 issuitably secured to the column 286 and is provided with a plurality ofarcuately spaced notches 283, 284, 285, 286, and 281 for receiving anarcuately movable lever 288 swingably mounted at 289. A Bowden wire 296operatively connects the lever 288 with the member 219 for simultaneousreciprocation of the valves and 254 for controlling the pump pressuredelivery and selectively operating the speed ratio controlling devicesof the transmission C in the manner hereinafter set forth.

Positioning of the lever 285 in notch places the transmission in neutralcondition. sothat power is not transmitted therethrough, while placingthe lever in notches 284, 285, 286 and 281 effects operation of thespeed control devices 35, 32', 33' and 34' respectively, in the wellknown manner. As illustrated, the lever 288 is engaged in notch 285 foroperation of the first speed ratio controlling device 32 for low speedoperation, such device requiring a higher degree of fluid pressure thanthe second and third speed devices 33' and 34' respectively.Manipulation of the lever to the position indicated reciprocates thepiston 253 sothat the chamber 255 communicates with the ports 25%) and259 and fluid pressure is supplied through conduits 26! and 262 to thepiston ZOI and 262, respectively, for eflecting a fluid pressuredelivery of the pump H to provide suitable operation of the device 32'.The piston 254 is simultaneously moved to the position indicated so thatthe annular groove 254 registers with the ports 255 and 269 and fluidpressure is communicated to the cylinder 238 through the conduit 213 foroperating the pistons 239 and 246, thus causing the band 35 to arrestrotation of the drum 31' of the device 32. Any fluid which may have beenpreviously supplied to the operating mechanism for the devices 33 and34' with return through the ports 210 and 21! respectively, due to theaction of the spring 231, and be evacuated from the cylinder 252 throughthe bleed 216 and communicated to the reservoir I24. In the event thereverse speed ratio controlling device has been previously operated,fluid returning to the chamber 252 through the port 268 will beevacuated through the port 216 for communication to the reservoir 124'.

When the second and third speed ratio controlling devices 33 and 34'respectively are operated the valves 253 and 254 are simultaneouslymoved so that each of the ports 258, 259 and 256 are in communicationwith the chamber 256 and fluid is communicated to each of the pistons26!, 262 and 253 and the swash plate i9! is moved upwardly to effect areduction of fluid pressure delivery of the pump, it being understoodthat these speed ratio controlling devices do not require as great afluid pressure as that required for the satisfactory operation of thefirst speed ratio controlling device. In the event that the second speedratio controlling device is selected, the groove 254 of piston 254establishes communication between the ports 266 and 210, and fluidreturning to the cylinder 252 from the cylinder 238 of the first speedratio controlling device 32 through the port 269 is evacuated throughthe port 216 to the fluid reservoir i242 In the event the third speedratio controlling device 34 is selected, the groove 254 establishescommunication between the ports 261 and 21l and fluid returning to thecylinder 252 from either of the ports 210, 259 or 268 is evacuatedthrough the port 216 When the reverse speed ratio controlling device 35is selectively operated, the valves 253 and 254 are again simultaneouslymoved by manipulation of lever 288 to the notch 266, the valve 253closing ports 259 and 260 against communication with the chamber 255,port 258 being open and pressure fluid communicated to the piston 20!only. It will be apparent that a greater fluid pressure acting throughthe piston 2M will be required to level off the swash plate l9! thatwill be required for a similar action, by the pistons 2M and 252 forfirst speed operation and 20!, 262 and 263 for second and third speedoperation. When the lever 288 is positioned, as aforesaid, the groove254 of valve 254 registers with ports 261 and 2H for communicating fluidthrough the conduit 212 to the cylinder 238 of the control device 35selected. Fluid returning from the cylinder 238 of the previouslyoperated speed ratio device is evacuated from the cylinder 252 throughthe ports 215 or 216.

When the lever is positioned in the notch 263 and the transmission is inneutral position by reason of the fact that the groove 25 i no longerregisters with either of the ports 268, 269, 216 or 21! and fluid isreturned to the reservoir i2 1.

Various modifications and changes will be apparent from the teachings ofour invention, as defined in the appended claims, and it is not ourintention to limit our invention to the particular details ofconstruction and mode of operation shown and described for illustrativepurposes.

What we claim is:

1. In a motor vehicle transmission having a plurality of speed ratiocontrolling devices, pressure fluid actuated means for selectivelyoperating said devices, manually operable means for controlling theselective operation of said pressure fluid actuated means, meansincluding a pump for supplying pressure fluid to said actuated means,means including a swingingly mounted wabble plate structure forcontrolling the pressure of fluid delivered by said pump, a plurality ofpressure fluid actuated pistons for controlling movement of said wabbleplate structure in one direction only, valve mechanism for controllingthe pressure fluid actuation of said pistons, and means responsive tothe operation of said manually operable means for actuating said valvemechanism.

2. In a motor vehicle transmission having a plurality of speed ratiocontrolling devices, pressure fluid actuated means for selectivelyoperating said devices, manually operable means for controlling theselective operation of said pressure fluid actuated means, meansincluding a pump for supplying pressure fluid to said actuated means,means including a swingingly mounted Wabble plate structure forcontrolling the pressure of fluid delivered by said pump, a plurality ofpressure fiuid actuated pistons for controlling movement of said wabbleplate structure in one direction only, and means responsive to theselective operation of one of said devices for causing the selectiveoperation of said pistons.

3. In a motor vehicle transmission having a plurality of speed ratiocontrolling devices pressure fluid actuated means for selectivelyoperating said devices, manually operable means for controlling theselective operation of said pressure fluid actuated means, meansincluding a pump for supplying pressure fluid to said actuated means,said pump comprising a plurality of reciprocating pistons, a wabbleplate structure controlling movement of said pistons, a plurality ofselectively operable pressure fluid actuated pistons acting on saidstructure in opposition to said pump pistons, and valve means operablein response to the operation of said manually operable means forcontrolling the selective operation of said fluid actuated pistons.

4. In a motor vehicle transmission having a plurality of speed ratiocontrolling devices, pressure fluid actuated means for selectivelyoperating said devices, manually operable means for controlling theselective operation of said pressure fluid actuated means, meansincluding a pump for supplying pressure fluid to said actuated means,said pump ccmprising a plurality of reciprocating pistons, a wabbleplate structure controlling movement of said pistons, a plurality ofselectively operable pressure fluid actuated elements acting on saidstructure in opposition to said pump pistons, said elements being sodisposed with respect to said wabble plate structure that selectiveactuation thereof will effect a variation in the control of said pumppistons by said wabble plate structure, and valve means for selectivelycontrolling the actuation of said elements.

5. In a motor vehicle transmission having a plurality of speed ratiocontrolling devices, pressure fluid actuated means including a commonoperating member for selectively operating said devices, manuallyoperable means for controlling the selective operation of said operatingmember, means including a pump for supp-lying pressure fluid to saidmember, said pump comprising a plurality of reciprocating pistons, awabble plate structure controlling movement of said pistons, a pluralityof selectively operable pressure fluid actuated elements acting on saidstructure in opposition to said pump pistons, said elements being sodisposed With respect to said structure that selective actuation thereofWill efiect a variation in the control of said pump pistons by saidstructure, and valve means operable by said member for selectivelycontrolling the actuation of said elements.

6. In a motor vehicle transmission having a plurality of speed ratiocontrolling devices, pressure fluid actuated means including a commonoperating member for selectively operating said devices, manuallyoperable means for controlling the selective operation of said operatingmember, means including a pump for supplying pressure fluid to saidmember, said pump comprising a plurality of reciprocating pistons, awabble plate structure controlling movement of said pistons, a pluralityof selectively operable pressure fluid actuated pistons acting on saidstructure in opposition to said pump pistons, and valve means operableby said member for controlling the selective operation of said fluidactuated pistons.

7. In a motor vehicle transmission having a plurality of speed ratiocontrolling devices, pressure fluid actuated means including a commonoperating member for selectively operating said devices, manuallyoperable means for controlling the selective operation of said operatingmember, means including a pump for supplying pressure fluid to saidmember, said pump comprising a plurality of reciprocating pistons, awabble plate structure controlling movement of said pistons, a pluralityof selectively operable pressure fluid actuated pistons acting on saidstructure in opposition to said pump pistons, and valve means forselectively controlling the pressure fluid actuation of said pistons,said valve means being operable by said member for selectively varyingthe action of said fluid actuated pistons on said wabble plate structurein response to the selective operation of said member by said manuallyoperable means.

8. In a motor vehicle transmission having a plurality of speed. ratiocontrolling devices, pressure fluid actuated means for selectivelyoperating said devices, valve means for controlling the selectiveoperation of said pressure actuated means, a manually operable means forselectively operating said valve means, means including a pump forsupplying pressure fluid to said actuated means, said pump comprising aplurality of reciprocating pistons, a wabble plate structure controllingmovement of said pistons, a plurality of selectively operable pressurefluid actuated elements acting on said structure in opposition to saidpump pistons, said elements being so disposed with respect to saidstructure that selective actuation thereof will effect a variation inthe control of said pump pistons by said structure, and valvemeans forselectively actuating said elements, said last named valve means beingoperable by said manually operable means in timed relation to theselective operation thereby of said first mentioned valve means.

9. In a motor vehicle transmission having a plurality of speed. ratiocontrolling devices, pressure fluid actuated means for selectivelyoperating said devices, manually operable means for controlling theselective operation of said pressure fluid actuated means, meansincluding a pump for supplying pressure fluid to said actuated means,said pump comprising a plurality of reciprocating pistons, a wabbleplate structure controlling movement of said pistons, a plurality ofselectively operable pressure fluid actuated pistons acting on saidstructure in opposition to said pump pistons, valve means operable bysaid manually operable means for selectively communicating pressurefluid to said devices, anc a second valve means for selectivelycommunicating pressure fluid to said fluid actuated pistons, said secondvalve means being operable by said manually operable means for varyingthe action of said fluid actuated pistons on said wabble plate structurein timed relation to the selective opera tion of one of said devices.

10. In a motor vehicle transmission having a plurality of speed ratiocontrolling devices, pressure fluid actuated means for operating saiddevices, manually operable means for controlling the selective operationof said pressure fluid actuated means, means including a pump supplyingpressure fluid to said actuated means, a swingably mounted wabble platestructure for controlling the pressure of fluid delivered by said pump,a plurality of pressure fluid actuated pistons for controlling movementof said wabble plate structure in one direction only, valve means forselectively communicating pressure fluid to said devices, a second valvemeans for selectively communicating pressure fluid to said pistons, andmeans responsive to the operation of said manually operable means foractuating said first and second valve means in a predetermined timedrelation.

11. In a motor vehicle transmission having a plurality of fluid pressureoperated speed ratio controlling devices, means controlling selectiveoperation of said devices, means including a pump for supplying a fluidunder operating pressure for operation of said devices, means includinga swingingly mounted wabble plate structure for controlling the pressureof fluid delivered by said pump, a plurality of pressure fluid actuatedpistons for controlling movement of said wabble plate structure in onedirection only, and valve means responsive to operation of said controlmeans for controlling fluid pressure actuation of said pistons.

12. In a motor vehicle transmission having a plurality of fluid pressureoperated speed ratio controlling devices, means controlling selectiveoperation of said devices, means including a pump for supplying a fluidunder operating pressure for operation of said devices, means includinga swingingly mounted wabble plate structure for controlling the pressureof fluid delivered by said pump, a plurality of pressure fluid actuatedelements for controlling movement of said wabble plate structure in onedirection only, and means responsive to the selective operation of oneof said devices for causing the selective operation of said elements.

13. In a motor vehicle transmission having a plurality of fluid pressureoperated speed ratio controlling devices, means controlling selectiveoperation of said devices, means including a pump for supplying a fluidunder operating pressure for operation of said devices, said pumpcomprising a plurality of reciprocating pistons, a wabble platestructure controlling movement of said pistons, a plurality ofselectively operable pressure fluid actuated pistons acting on saidstructure in opposition to said pump pistons, and valve means operablein response to the operation of said control means for controlling theselective operation of said fluid actuated pistons.

14. In a motor vehicle transmission having a plurality of fluid pressureoperated speed ratio controlling devices, means controlling selectiveoperation of said devices, means including a pump for supplying pressurefluid under operating pressure for operation of said devices, said pumpcomprising a plurality of reciprocating pistons, a wabble platestructure controlling movement of said pistons, a plurality ofselectively operable pressure fluid actuated elements acting on saidstructure in opposition to said pump pistons, said elements being sodisposed with respect to said wabble plate structure that selectiveactuation thereof will effect a variation, in the control of said pumppistons by said wabble plate structure,

and valve means for selectively controlling the actuation of saidelements.

15. In a motor vehicle transmission having a plurality of fluid pressureoperated speed ratio controlling devices, manually operable meansoperable to effect selective operation of said devices, means includinga pump for supplying a fluid under operating pressure for operation ofsaid devices, said pump comprising a plurality of reciprocating pistons,a wabble plate structure controlling movement of said pistons, aplurality of selectively operable pressure fluid actuated elementsacting on said structure in opposition to said pump pistons, and valvemeans operable by said manually operable means for controlling theselective operation of said fluid actuated elements.

16. In a power transmitting mechanism including a plurality of fluidpressure operated speed ratio control devices, a pump for supplying afluid under operating pressure for operation of said devices, a wabbleplate movable to vary the fluid delivery output of said pump, aplurality of fluid pressure actuated elements operable to move saidplate in one direction, valve means operable to eflect distribution ofpressure fluid to said devices, means operable to effect operation ofsaid valve means, and means responsive to operation of the means toeffect operation of said valve means for controlling operation of saidfluid pressure actuated elements.

17. In a power transmitting mechanism including a plurality of fluidpressure operated speed ratio control devices, a pump for supplying afluid under operating pressure for operation of said devices, a wabbleplate movable to vary the fluid delivery output of said pump, aplurality of elements operable to move said plate in one direction,valve means operable to effect distribution of pressure fluid to saiddevices, means operable to effect operation of said valve means, andmeans responsive to operation of the means to effect operation of saidvalve means for effecting selective operation of said elements.

18. In a power transmitting mechanism including a plurality of fluidpressure operated speed ratio control devices, valve means operable toeffect distribution or" pressure fluid to said devices, control meansoperable to eiiect operation of said valve means, a variably operablepump for supplying a fluid under operating pressure for operation ofsaid devices, means operable to vary the operation of said pump, saidlast named means including a plurality of elements operable by thepressure of fluid delivered by said pump, and valve means operable inresponse to operation of said control means for effecting selectiveoperation of said elements.

19. In a power transmitting mechanism including a plurality of fluidpressure operated speed ratio control devices, valve means operable toeflect distribution of pressure fluid to said devices, means operable toeffect operation of said valve means, a variable operable pump forsupplying a fluid under operating pressure for operation of saiddevices, means operable to vary the operation of said pump, said lastnamed means including a fluid pressure actuated element, and valve meansoperable to eflect operation of said element, said last mentioned valvemeans being operable in timed relationship to operation of the meansoperable to eflect operation of said first mentioned valve means.

WILLIAM T. DUNN. OTTO W. SCHOTZ.

